Disciplines / Research questions

Physics

691 research topics · 2739 questions

Markov transition matrix and XXZ Hamiltonian1 questions
  1. Constructing an integrable stochastic process associated with the twisted D2(2)D_2^{(2)} algebra

massive Ising field theory2 questions
  1. First-principles derivation of Zamolodchikov's E8 S-matrix and of the infinite towers of higher-spin integrals of motion for the Ising model in a magnetic field

  2. Complete analytic characterization of the universal scaling function of the two-dimensional Ising model in a magnetic field

matrix product operators(MPO)3 questions
  1. Exact diagonalization of two-dimensional transfer operators (PEPOs) for three-dimensional models exhibiting phase transitions

  2. Hopf-algebraic solvable unitary circuits: the bialgebra converse conjecture and the finite-exponent conjecture for C*-weak Hopf algebras

  3. Controlled compression theory for local matrix product operators beyond first degree: second-degree operators, global truncation error, QR-iteration convergence, and precision-stable iterative compression

matrix product states(MPS)2 questions
  1. Completing boundary integrability from the fuzzy three-sphere: so2n\mathfrak{so}_{2n}-symmetric integrable matrix product states, sibling chains, and the quantum and holographic status of fuzzy-sphere defects

  2. Finn–Vanicat Conjecture 4.1: the m→∞m\to\infty limit of Koornwinder matrix-product states and an effective exact formula for the current cumulant generating function of the open ASEP

monodromy matrix2 questions
  1. Q-operator, exceptional parameter loci, and correlation functions for the cyclic Bazhanov–Stroganov representations of the 6-vertex reflection algebra

    Open for about 10 years
  2. Correlation-function building blocks for the open XXZ spin-1/2 chain with general integrable boundaries: the overlap factor, form factors, and the inverse problem

    Open for about 5 years
Circulation solutions of the Navier–Stokes and Euler equations relevant to natural disasters8 questions
  1. Open problems for the Coriolis-based gas dynamics of destructive atmospheric vortices: simulation fidelity, selection of a persistent vortex, planetary-rotation regimes, and energy feasibility of usage and mitigation

    Open for about 7 years
  2. Robustness of the quasi-cyclostrophic regime predictions for tornado formation to realistic atmospheric processes

    Open for about 5 years
  3. Tropical cyclone boundary layer shocks beyond the formation time: post-shock theory, shock-strength criteria, translating-storm geometry, and merger dynamics

    Open for about 9 years
  4. Circulation sources of dust devil-like vortices: midlevel generation by convective organization and its extension to realistic dust devils

    Open for about 13 years
  5. Modular analysis of tropical-cyclone structure beyond the boundary layer: the saturated inviscid core, eyed vortices, and the corner flow

    Open for about 12 years
  6. Rigorous justification of the formal perturbation series for stationary powerful-tornado solutions of the reduced Navier–Stokes system, and the role of the Coriolis force in it

    Open for about 5 years
  7. Extending the Li–Sinai renormalization-group blow-up theory for the 3D incompressible Navier–Stokes equations to non-axisymmetric fixed points and to real antisymmetric solutions

    Open for about 6 years
  8. Self-consistent analytical modelling of tornado-like vortex velocity and surface-pressure fields across swirl ratios (the Gillmeier–Sterling–Hemida–Baker benchmark)

    Open for about 8 years
Onsager algebra1 questions
  1. Generalized Onsager algebras: irreducible modules beyond one-dimensional characters and the classified finite-dimensional cases, and inhomogeneous Serre presentations beyond symmetrizable Cartan matrices

    Open for about 7 years
Onsager free energy2 questions
  1. Direct derivation of the finite-size-scaling limit of the square-lattice Ising model on the open rectangle: the surface–corner scaling function and the critical lattice–CFT modular correspondence

    Open for about 9 years
  2. Exact analytic theory of the finite-size expansions of the critical internal energy and specific heat of the two-dimensional Ising model with free boundaries

    Open for about 13 years
operator spreading2 questions
  1. Operator spreading in single-particle quantum maps: the open-problem bundle of operator hydrodynamics, randomization, spectral-form-factor timescales, basis dependence, emergent classicality, and extensions to scars

  2. Quasi-local soliton-gas mappings, ancestry algorithms, and sharp logarithmic operator-entanglement growth in interacting integrable quantum systems beyond the Rule 54 chain

parafermion1 questions
  1. Exact correlation functions and their disorder distributions in random free-parafermion chains

parafermionic CFT1 questions
  1. Statistical interaction matrices for higher-rank level-2 parafermion theories and the resulting Rogers–Ramanujan-type q-identities

Perron–Frobenius property1 questions
  1. Perron–Frobenius degrees of Perron numbers: which data control the minimal dimension of a non-negative integral matrix realization (Yazdi, Questions 5.1–5.4 and Remark 3.9)

    Open for about 5 years
Pfaffian partition function2 questions
  1. Minimum number of Pfaffians representing the Ising partition function of a non-planar graph

    Open for about 12 years
  2. Closed-form dimer-monomer generating function for a single monomer at an interior site of the square lattice (Wu's interior-monomer problem)

    Open for about 20 years
Poisson summation formula4 questions
  1. Sharp hypotheses and the maximal generalized theta-series class for the dimensionally continued Poisson summation formula

  2. I-Bessel lattice sums in natural generality: convergence classification of plain sums, twisted Poisson summation without the divisibility hypothesis, and continuum limits at general scalings

  3. Ground states of pair potentials with nonnegative compactly supported Fourier transform: the regimes below the threshold density, above close packing, and the bcc–fcc window

  4. Rigorous foundations for the angular-averaged (Yakub-Ronchi) Ewald potential derivation: the lattice-sum identity S(k)=δ1,kS(k)=\delta_{1,k} and the Euler-Maclaurin-to-Poisson function class in three dimensions

Potts critical manifold3 questions
  1. Analytic theory of the critical-polynomial method for Potts critical manifolds: finite-size scaling exponents, antiferromagnetic zero loci, and the limits of applicability

    Open for about 10 years
  2. Convergence, exactness, and the antiferromagnetic phase diagrams of the critical-polynomial method for two-dimensional Potts models

    Open for about 14 years
  3. Exact critical manifold of the q-state Potts model on the kagome lattice and the convergence of its critical polynomials

    Open for about 46 years
Potts critical exponents3 questions
  1. Conformal field theories and critical exponents of the exact scattering solutions for the two-dimensional random-bond q-state Potts model

    Open for about 9 years
  2. Upper critical dimension of the 3-state Potts model: pinning down dcrit(q=3)d_{\rm crit}(q=3) and the termination of its critical and tricritical fixed points

    Open for about 45 years
  3. Magnetic critical exponent of the two-dimensional Potts model with long-range correlated bond disorder beyond leading perturbative order

    Open for about 2 years
Planar duality of the Potts model3 questions
  1. Criticality of the self-dual point for random-cluster and Potts models on planar self-dual polygon configurations

    Open for about 20 years
  2. Duality criterion for the three-state Potts antiferromagnet on plane quadrangulations: rigorous proof or classification of exceptions

    Open for about 8 years
  3. Exact critical frontiers for the Potts and percolation models beyond the ferromagnetic triangular-decomposition class

    Open for about 44 years
Potts partition function3 questions
  1. Is the ferromagnetic Potts partition function AP-reducible to #BIS? The open converse in the Goldberg–Jerrum #BIS-hardness result for Tutte(q,γ), q>2, γ>0

    Open for about 16 years
  2. Chromatic-count conjectures and the infinite-width limit of partition-function zeros for Potts models on honeycomb-lattice strips

    Open for about 19 years
  3. Tutte-Beraha crossings of the partition-function-zero loci of the restricted Potts model on lattice strips (Chang-Shrock conjecture)

    Open for about 20 years
Potts latent heat1 questions
  1. Ferromagnetic Potts model on the Betts (maple leaf) lattice: the q=4 magnetization-exponent anomaly and the unquantified weak first-order q=5 transition

    Open for about 20 years
Potts and Ashkin-Teller Models4 questions
  1. Fixed-point structure of the pseudo-critical three-dimensional three-state Potts transition: the thermodynamic-limit scaling dimension of the subleading singlet ϵ′\epsilon' and the identity of the governing multicritical or complex fixed point

    Open for about 1 year
  2. Nature of the phase-transition line of the three-dimensional Ashkin–Teller model: non-universality, wide crossover, or emergent-O(2) universality?

    Open for about 46 years
  3. Defect magnetic critical behaviour of the two-dimensional Ashkin–Teller model with an asymmetric line defect

    Open for about 17 years
  4. Criticality and conformally invariant scaling limits of the planar random-cluster model for 0<q<10<q<1 and for 1<q≤41<q\le4, q≠2q\ne2

    Open for about 16 years
prethermalization2 questions
  1. Quantitative theory of fractionalized prethermalization in the driven one-dimensional Hubbard model: lifetime crossover, drive-class boundaries, and a controlled time-dependent Schrieffer-Wolff expansion

  2. Meson-number-violating kinetic theory and interacting-meson prethermalization in confined one-dimensional quantum systems

projected entangled-pair states(PEPS)2 questions
  1. Can projected entangled-pair states represent interacting (2+1)-dimensional chiral topological phases?

  2. The complexity landscape of injective PEPS: the translation-invariant case, threshold sharpness, and the learning analogue

pseudoenergy2 questions
  1. Exact derivation of the thermodynamic Bethe ansatz equations from the S-matrix/filling-fraction formalism for quantum gases

  2. The general finite-volume boundary state: overlaps and excited-state g-functions in integrable QFT beyond diagonal scattering and bulk-only perturbations

Non-perturbative dynamics of QCD6 questions
  1. Is vertex-dressing-function analyticity forced? The phase constraint behind confinement from the QCD effective charge

    Open for less than 1 year
  2. Rigorous establishment of the gluon-condensate route to confinement in Yang-Mills theory

    Open for about 1 year
  3. Axion-meson mixing and the axion-photon coupling at next-to-next-to-leading order in U(3) chiral perturbation theory

    Open for about 3 years
  4. Universality class of the chiral phase transition in (2+1)-flavor QCD and the fate of effective UA(1)U_A(1) symmetry at Tc0T_c^0 in the chiral limit

    Open for about 42 years
  5. Open questions on Cheshire θ\theta terms: UV origin, the Skyrme-current–η′\eta' coupling in large-NcN_c QCD, and their physical consequences

    Open for about 1 year
  6. Completing the anomaly-matching proof of chiral symmetry breaking in QCD-like theories: the heavy-quark continuity gap for Nf<pmin⁡N_f<p_{\min} and generalization beyond SU(Nc)SU(N_c) fundamentals

    Open for about 46 years
Phase structure of QCD at finite temperature and density and strongly coupled quark matter4 questions
  1. Reentrant first-order deconfinement transition at high baryon density in heavy-quark lattice QCD and the connection between heavy- and light-quark first-order boundaries

    Open for about 1 year
  2. Microscopic determination of the in-medium quark couplings of cold dense quark matter — vector repulsion, flavor-non-singlet vector couplings, and diquark coupling — from nonperturbative gluon exchange

    Open for about 7 years
  3. Quantitative phase structure of QCD at finite temperature and chemical potential: partial deconfinement, baryon condensation, and the QCD critical point

    Open for about 1 year
  4. Mapping the chiral-spin-symmetric (stringy-fluid) band of the QCD phase diagram: the quantitative upper boundary at finite baryon chemical potential, its fate at large density, and the order of the inter-regime transitions

    Open for about 4 years
quantum affine algebra4 questions
  1. Simplicity of tensor products of Kirillov-Reshetikhin modules for the non-nested interval collections of Kanakubo-Koshevoy-Nakashima (Conjecture 7.11)

    Open for about 1 year
  2. Completeness of the Bethe ansatz and rationality of Baxter polynomials for twisted transfer-matrices of quantum affine algebras

    Open for about 12 years
  3. Freidel–Maillet type presentations beyond the positive part of Uq(sl2^)U_q(\widehat{sl_2}): the equitable-type presentation of the full quantum affine algebra, higher-rank extensions, and the complete Hopf isomorphism between its Drinfeld–Jimbo and Drinfeld realizations

    Open for about 5 years
  4. Irreducibility criterion for tensor products of a snake module with an arbitrary simple module over quantum affine slk\mathfrak{sl}_k (Bittmann–Li Conjectures 5.10 and 5.6)

    Open for about 4 years
quantum determinant3 questions
  1. Commutativity of quantum elementary symmetric polynomials in half-quantum algebras

    Open for about 13 years
  2. Commutativity of antidiagonal quasi-determinants in the reflection equation algebra for arbitrary rank (Talalaev's Hypothesis 2.6)

    Open for about 2 years
  3. Centrality of the quantum hyperdeterminant: constructing the quotient algebra of quantum hypermatrices in which Det⁡q\operatorname{Det}_q becomes central

    Open for about 11 years
quantum group Uq(g)U_q(\mathfrak g)3 questions
  1. The alternating universal K-matrix for the q-Onsager algebra: construct a universal K-matrix for the alternating central extension AqA_q from solutions of a universal Freidel-Maillet type equation, or prove that none exists

    Open for about 5 years
  2. Weyl-group invariance of the quantum group image in the cluster realization of higher Teichmüller theory

    Open for about 7 years
  3. Higher Frobenius–Schur indicators of small quantum groups: effective formulas for uq(g)u_q(\mathfrak{g}) beyond sl2\mathfrak{sl}_2 and the gcd-divisibility of νn(H)\nu_n(H)

quantum KdV3 questions
  1. All-orders shifted symmetric structure of the quantum KdV eigenvalues (Conjecture 1.9 of van Ittersum–Ruzza)

  2. Extend the meromorphic-differential/double-ramification correspondence from the trivial and Hodge CohFTs to general cohomological field theories satisfying the strata vanishing conditions

  3. Irreducibility, genus, and global geometry of the spectral curves of the quantum KdV hierarchy

quantum transfer matrix3 questions
  1. Correlation functions of the integrable SU(n)SU(n) spin chain: analytic three-site evaluation, extension to m≥4m\ge 4 and n>3n>3, and finite-temperature computation

  2. Completing the rigorous low-temperature spectral theory of the quantum transfer matrix of the massless XXZ spin-1/2 chain

  3. Completing the Riemann-Hilbert formulation of the finite-temperature one-dimensional Hubbard model: low temperatures, strong coupling, and excited thermodynamic branches

quench action3 questions
  1. Universality conditions for the charge full counting statistics of quenched one-dimensional quantum gases

  2. Explicit generalized Gibbs ensemble and generalized detailed balance for post-quench stationary states with algebraic rapidity tails

  3. Exhaustiveness of the boundary K-matrix construction: classification of integrable initial states and integrable matrix product states of Bethe-ansatz spin chains

Rapidity distribution3 questions
  1. Quantitative extraction of the local rapidity distribution of a 1D Bose gas from finite-time slice expansion: controlled systematics, inference beyond thermal ansätze, and the fitted-temperature anomaly

  2. Finite-interaction dynamics after a strong Bragg quench in 1D Bose gases and the validity of generalized hydrodynamics during local prethermalization

  3. The atom-loss functional F[ρ](k)F[\rho](k) of the one-dimensional Bose gas: evaluation beyond the asymptotic regimes and loss-driven rapidity dynamics

rapidity curve4 questions
  1. Equivalence classification of N-state chiral Potts models under the modular rapidity symmetry group

    Open for about 13 years
  2. The generalized order-parameter function Gpq(r)G_{pq}(r) of the solvable chiral Potts model at arbitrary rapidities

    Open for about 28 years
  3. Discrete-spin solutions of the star-triangle relation from root-of-unity limits beyond the ZN\mathbb{Z}_N-symmetric family

    Open for about 8 years
  4. Non-perturbative derivation of the generalized chiral Potts model R-matrix from four-dimensional Chern-Simons theory

    Open for about 1 year
rapidity line4 questions
  1. First-principles ODE/IQFT derivation and the quantization-condition conjecture for the staggered six-vertex model with Uq(sl(2))U_q(\mathfrak{sl}(2))-invariant open boundary conditions

    Open for about 2 years
  2. Root locations of the XXZ Bethe Ansatz equations: the unproven intermediate anisotropy regime and the N≥3N\ge 3 magnon sectors

    Open for about 11 years
  3. Descendants of the six-vertex model from the Drinfeld doubles of dihedral group algebras: analytic proofs of the all-nn Yang-Baxter conjectures and the Fateev-Zamolodchikov limit

    Open for about 16 years
  4. Exact continuum limit and symmetry structure of the staggered six-vertex model

    Open for about 19 years
reflection equation2 questions
  1. Set-theoretical reflection maps: geometric reinterpretation of the quadrirational classification, discrete soliton-boundary scattering, and set-theoretic quadratic boundary algebras

  2. Completeness of the orbifold gauge-theory construction of quasi-classical elliptic and trigonometric K-matrices and the classification of classical k-matrices

Regularity, unitarity, and crossing3 questions
  1. Rigorous partial-wave positivity classification of the hypergeometric amplitude: the positive-mass-squared islands, the root-spacing conjecture, and the analytic–numerical gap

    Open for about 3 years
  2. Bootstrap classification of Regge-slope spectral densities for unitary dual-resonance S-matrices

    Open for less than 1 year
  3. Origin of the gap to Jin-Martin maximal growth in the dispersive primal S-matrix bootstrap

    Open for about 1 year

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